Securing carbons



(No Model.)

E. L. SHARPNEGK 8v W. @SI-IEDE.

SEGURI'NG GARBONS.

No. 473,479. Patented Apr. Z6, 1892.

UNITED STATES PATENTl OFFICE.

ELIEL L. SHARPNECK, OF DENVER, AND WILLIAM G. SI-IEDD, OF LEADVILLE,COLORADO.

SECURING CARBONS.

SPECIFICATION forming part of Letters Patent No. 473,479, dated April26, 1.892. Application filed January 15, 1889. Renewed November 2, 1891.Serial No. 410.659. (No model.)

To @ZZ whom it r11/cry concern.-

Beit known that we, ELIEL L. SHARPNECK, residing at Denver, in thecounty of Arapahoe, and WILLIAM G. SHEDD, residing at Leadville, in thecount-y of Lake, State of Colorado, citizens of the United States, haveinvented certain new and useful Improvements in Means for SecuringOarbons, of which the following is a specification, reference being hadtherein to the accompanying drawings.

This improvement relates to that class` of tools in which cai-bons,black diamonds, or similar articles are set in soft metal inclosed orpartially inclosed in a harder metal; and the invention consists,mainly, in a tool having carbons or their equivalents set inp'rojections formed integral with the body of the holder and protectedby a shield of harder metal.

In carrying out our invention for drilling purposes we prefer to use thedevice hereinafter more fully described, and illustrated in theaccompanying drawings, in which- Figure l is a perspective View of acarbonholder constructed according to our im provenient ready for use;Fig. 2, an end View of the saine; Fig. 3, a perspective view of themainl portion of the bit Without the shield, and Fig. 4t a plan of theshield detached.

Referring now to the details of construction, A indicates the bit, (oftubular form in this instance,) provided with a series ot'partially-cylindrical projections a, generally setin two concentriccircles. The projections are preferably formed on the bit by means of ahollow tool in a manner well understoodv by machinists and preferablyafter the diamonds or cai-bons have iirst been embedded in the bit; butthey may be formed on or attached to the bit in any convenient way. Inthese projections the carbons or diamonds are set in the usual manner,preferably before the intervening soft metal of the bit is cut away, asabove set forth, and over these projections a hard-metal shield B isplaced, having recesses b to receive the projections o. This shield ispreferably made of the best drill-steel, very highly tempered, and thusmakes a perfect protection to the softer metal Ain which the diamondsare embedded, so that the carbons are more securely held in place andtheir loss prevented and the trouble of frequently resetting and theloss of time spent in resetting them under the old way of setting isavoided. The shield may be fastened on in any convenient way; but we prefer to make it tightly fit t-he projections and then drive or force iton. Should it be too loose to hold on in this way, one or more ot thesoft-metal projections may be slightly upset by a light blow on a punchor hard chisel Von the side near the joint between the hard and softmetals.

While we have referred to carbons or diamonds, it is evident that otherhard stones or substances-such as Brazilian borts, points, drm-may beused in the same manner and for the same purpose.

We do not of course limit ourselves to the use of bits for drilling, butour invention may be applied to saws or other devices for cutting,boring, or dressing purposes, or to any purpose to which such carbons orother hard substances may be applied.

What we claim as new is l. A tool having a series of carbons securelyfastened in and held in immediate contact with soft-metal projectionsformed integral with said tool and a shield of harder metal partiallyinclosing said soft-metal projections and protecting them from wear,substantially as described.

2. A tool having a series of projections arranged at different distancesfrom its center, carbons set in the inner and upper faces of the innerprojections and in the outer and upper faces of' the outer projections,and a hardened shield arranged on the sides of the projections oppositethe carbons and par tially surrounding the same, substantiallyasdescribed.

3. A bit A, having the carbons set in projections a of soft metal,arranged in multiplex circles, and a ring shield or protector B, havingrecesses b formed in opposite sides of the body of said ring and fittingsaid projections, all constructed and arranged substantially asdescribed.

In testimony whereof we affix our signatures, in presence of twowitnesses, this 10th day of January, 1889.

ELIEL L. SHARPNECK.

` WILLIAM G. SHEDD.

Witnesses:

CHARLES B. SHEDD, JOHN S. FIELD.

IOO

